"Kim loves Tristan, so she is super supportive," the anonymous insider said. "She couldn't be more happy for the family."

"Kim can't wait to be an aunt again," the source added. "She knows most of her sisters want big families and that is exactly what seems to be happening. She loves witnessing the family blossom."

The KarJenner clan definitely looks to be in the process of expanding. Both Khloe and sister Kylie Jenner are reportedly due to give birth in early 2018, though neither of them have confirmed the pregnancy rumors yet. Meanwhile, Kim confirmed just this week that she and husband Kanye West are also expecting, though she made no mention of the surrogacy reports.